Apparatus and method of making clothespins



Oct. 11, 1955 R, A, HARRIS ET Al.

APPARATUS AND METHOD OF MAKING CLOTHESPINS Filed Oct. 17, 1952 IINVENTORS wal/A @a A A @fe/e, @a y f. CA fm,

United States Patent O APPARATUS AND METHOD F MAKING CLOTHESPINS RichardA. Harris and Roy E. Carr, High Point, N. C.;

said Richard A. Harris assignor of ten per cent to said Roy E. Carr andtwenty `per cent to E. W. Harris,

Sophia, N. C.

Application October 17, 1952, Serial No. 315,262

4 Claims. (Cl. 18-42) This invention relates to a method of apparatusfor making clothes pins and further relates to a clothes pin made by theuse of said method and apparatus.

One important object of the invention is to provide a novel method forthe construction of clothes pins whereby a spring wire clothes pin` maybe provided with plastic gripping jaws.

A second important object of the invention is to provide a novel methodwhereby a gang of such clothes pins may be formed at the same time andthereafter separated into single units.

A third important object of the invention is to provide a novel mold forsuch clothes pins and having a cap member arranged to hold the Wireportions of the clothes pin in laterally spaced relation. p v l A fourthimportant object of the invention isto provide a novel mold whereby eachend `of a spring `wire may be provided with a plastic gripping jaw.

A fth important object of the invention is to provide a mold of thischaracter which may be disassembled for removal from the plastic jaws.

A sixth important object of the invention is to provide means forseparating the individual clothes pins from a gang of such pins.

With the above and other objects in view, as will be hereinafterapparent, the invention consists in general of a novel method of formingclothes pins of the character above described, a novel mold apparatusfor carrying the method into execution and a novel article ofmanufacture in the shape of a clothes pin, all being fully described andillustrated in the accompanying drawings, and particularly claimed.

In the accompanying drawings like characters of reference indicate likeparts in the several views and;

Fig. l is a section on the line 11 of Fig. 2.

Fig. 2. is a longitudinal median vertical section on the center line ofFig. 1.

Fig. 3 is a section on the line 3-3 of Fig. 2.

Fig. 4 is a section on the line 4-4 of Fig. 2.

Fig. 5 is a vertical transverse section through the old parts, thespring wire frame and the molten plastic material.

Fig. 6 is a view taken transversely through a gang of the wire framesand illustrating the hardened plastic material in sections.

Fig. 7 is a view illustrating the step of separating the gang of pinsinto single units.

Fig. 8 is a side view of a completed pin as constructed in accordancewith the method and in the apparatus forming features of this invention.

Fig. 9 is a view taken from the right side of Fig. 8.

In the accompanying drawings there is shown a mold cap indicatedgenerally at 10, and shown in inverted position in Fig. 1 and in erectposition in Fig. 5. This cap has a top member 11 and side walls 12. Theinner surfaces of these side walls are provided with vertical grooves13, the grooves in each wall being spaced laterally from each other andthe grooves in one wall being opposite ICC the grooves in the otherwall. In connection with the capping member 10 there is provided asectional mold bottom indicated in general at 14. This mold bottomincludes a pair of mold sides 15 between which is litted a mold bottom16. This mold bottom has a rib 17 extending upwardly along the centerline of the bottom and the rib is provided with a narrow edge portion18. The upper part of the inner face of each wall 15 is cut away toprovide an outwardly daring portion 19, the lower edges of these flaringportions lying in the horizontal plane of the upper surface of the ribportion 18. Through the sides 15 and mold bottom 16 passes a bolt 20having a head 21. On this bolt is tted a swing nut 22, the head and wingnut bearing on the outer surfaces of the mold sides 15.

In the formation of the clothes pin there is provided a length of wirebent at its middle portion to provide a substantially dat end 20. Fromthe ends of this extends a pair of arms 21a. At the upper end of thesearms the wire is bent to provide cross-members 22. From each of theseextends a terminal portion 23, these being parallel upon insertion ofthe wire portion of the clothes pin in the mold cap, so that the arms21a lie in opposed grooves 12.

In use a series of these wire forms is placed in the mold cap while thecap is in the inverted position shown in Figs. l and 2, the arrangementof the wires in thel mold cap being also shown in Figs. 3 and 4. Whenall of the grooves of the mold cap have been filled, a supply of liquidplastic material such as is shown at 24 is provided in the mold bottom14`between each wall 15 and rib 17, and its reduced portion. 18, theplastic material filling the mold 14 to a level of the horizontal planewherein lies the top surface of the reduced portion 18 and the loweredges of the cutaway portions 19.

The cap and the bottom part 14 are then set aside and left until theplastic material becomes hardened or set. When this happens the mold capmay be removed, the nut 22 is then unscrewed from the bolt 20, the sides15 separated laterally and the mold bottom 16 drawn out from between theplastic masses. This will leave two strips of plastic mass sectionsthrough which are shown in Fig. 6 at 23 and a number of the wire formsprojecting upwardly therefrom as shown in Fig. 7., In order to separatethe individual clothes pins from these plastic strips we preferablyprovide a rapidly revolving shaft 24, on which is carried a series ofspaced circular cutter blades 25 preferably serrated to form saws. Thespacing of these cutter blades is identical with the spacing between thewire loops so that when the plastic masses 23 are brought into contactwith these blades, such masses are cut to have parallel faces and formjaws 25 of the proper shape to t over a clothes line and grip theclothes thereon.

It will be obvious that in the practice of the present invention thearms 21a will be compressed in the act of inserting the wire formationinto the mold cap 10 which not only places the wire formation undertension, but also serves to spread apart the terminal portions 23 of theformation. Thus, this procedure not only retains the wire formation inthe mold cap, but also permits the plastic tips to be molded on theterminal portions 23, while the latter are under tension and in spacedapart relation whereby when the tips have set the completed clothespinacts in the nature of a spring clamp.

It is obvious that minor changes may be made in the form of constructionof the apparatus and changes may also be made in the steps of the methodwithout departing from the material principles involved. Furthermore,the precise form of the finished clothes pin may be varied also withoutdeparting from the peculiar char- Patented Oct. 11, 1955` acteristicsthereof. It is not, therefore, desired to conne the invention to theexact form herein shown and de.- scribed, but it is wished to includeall such as properly come within the scope claimed.

We Claim:

l. A molding apparatus for forming plastic jaws on the free ends ofspring wire clips, each clip including a pair of free clamping ends andan integral loop portion connecting the ends and urging them relative toeach other, comprising an elongated mold having a bottorn Wall,upstanding side walls and an open top, a longi tudinally extending ribupstanding centrally from the bottom wall and dividing the mold into twoseparate cavities, each of which is adapted to contain a separate bathof liquid plastic material, said rib terminating in a reduced upper endat the upper level of the baths, a channel shaped holder including apair of opposed side walls and a wall connecting the side walls andadapted to form a top wall for the mold, said side walls of the holderseating on the upper ends of the side walls of the mold, each side wallof the holder being formed with longitudinally spaced transversegrooves, the grooves in the walls being aligned transversely of theholder to receive the sides of the loops of the clips and the grooves inthe walls being spaced apart transversely of the holder to compress theloops slightly and spread the ends of the clips apart, the ends of eachclip extending from the holder beyond the walls and being immersed inthe separate baths, said upper ends of the side walls of the moldextending above the upper end of the rib and having I their innersurfaces concaved to receive the juncture portions of the loop andclamping ends.

2. The method of forming plastic jaws on the free ends of a spring wireclip, which includes a pair of free ends and a loop connecting said endsand normally urging them relative to each other; comprising the steps ofpreparing separate side by side baths of liquid plastic material,compressing the loop of the clip to spread the ends apart, immersing theends of the clip in the separate baths while retaining them spread apartand allowing the material to set.

3. The method of forming plastic jaws on the free ends of spring wireclips, each of which includes a pair of free clamping ends and a loopsconnecting the ends and normally urging them relative to each other,comprising the steps of preparing separate side by side baths of liquidplastic material, assembling the clips in spaced fashion in a row,compressing the loops of the clips to spread the ends apart, immersingthe ends of the clips in the baths while retaining them spread apartWith the legs of each clip being in the separate baths, and allowing thematerial to set.

4. In the method of claim 3, the further step of simultaneously severingthe material between each clip.

References Cited inthe le of this patent UNITED STATES PATENTS 1,733,739Laukamp Oct. 29, 1929 1,770,298 Cannil July 8, 1930 1,782,447 ScrantomNov, 2,5, 1930 2,136,609 Buttereld Nov. 15, 1938 2,173,186 Swartz -1.,.,Sept. 19, 1939 2,436,597 Otis Feb. 24, 1948 ,2,445,537 vSchaeier July20, 1948 2,500,677 Harris Mar. 14, 1950 2,527,063 Heuer Oct. 24, 1950

